On Tue, Jan 18, 2000 at 12:11:16AM -0600, Bruce Guenter wrote:
> On Tue, Jan 18, 2000 at 12:53:37AM -0500, Russell Nelson wrote:
> > > Um, am I missing something? I thought the whole point of the "info"
> > > portion of the filename of the message in the maildir?
> > Right, and do you want the filename changing all the time? Instead of
> > a simple "open()", you have to do a "opendir(), readdir(), string match,
> > closedir()" set of syscalls. I suppose that you could attempt a
> > simple open() first, and then only if that fails do you go searching.
>
> I saw that from another message. Valid point. Perhaps the server would
> treat the observed filenames as a "cache" mapped by the unchanging
> portion. Any miss would cause a revalidation of all of them (since
> readdir typically issues only one syscall per many directory entries).
> This is basically what you described.
I'd say, indeed, a cache based on the unchanging part of the filename, always
doing full readdir() [or getdents(), depending on your UNIX], and then
gathering info from files that aren't in the cache already. Note that this is
from a MUA point of view (not even POP3, just MUA, that wants to work with
headers).
> I don't very much favor the idea of extending the Maildir structure just
> to add flags like that. On the other hand, such extensions are ideal
> for storing other persistent client (configuration) data.
I don't see the need for that..
> On the subject of extensions of Maildir, though, I had a bit of a
> radical thought: make each message a directory, containing one file for
> the headers, and one file per attachment. This has the benefit of
> pre-parsing attachments for processes like IMAP that want to be able to
> fetch just one of the parts, but at a significant cost. Fetching the
> entire message would cause quite a bit of conversion and repackaging.
> Searching now touches even more files. Every message now uses at least
> 3 inodes now instead of just one, with the side effect of increasing the
> amount of wasted (slack) space. More disk accesses to examine a
> mailbox.
Hmmm... I don't like this one:
- IMAP-stuff is still as complicated, delivery is _more_ complicated now.
- wasting inodes and therefore hindering NFS performance which is isn't so
good already for Maildir.
I see no benefits.
Greetz, Peter.
--
Peter van Dijk - student/sysadmin/ircoper/madly in love/pretending coder
|
| 'C makes it easy to shoot yourself in the foot;
| C++ makes it harder, but when you do it blows your whole leg off.'
| Bjarne Stroustrup, Inventor of C++
